Classnotes
Classnotes
Classnotes
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
English Maths. 2nd Year, European Section at Modesto Navarro. La Solana.<br />
5. Elimination or addition method.<br />
To learn the procedure to solve a system of equations using the elimination<br />
method, please visit these videos in the following websites:<br />
http://www.youtube.com/watch?v=xB-oXaCoJoc<br />
http://www.youtube.com/watch?v=ej25myhYcSg<br />
Solved example: Solve the system of linear equations.<br />
multiply all the terms in the second equation by 3<br />
-2x + 3y = 8<br />
9x - 3y = -15<br />
add the two equations (you can also subtract them if it is easier)<br />
7x = -7<br />
Note: y has been eliminated, hence the name: method of elimination. Now solve the<br />
above equation for x:<br />
x = -1<br />
replace x with -1 in the first equation:<br />
-2(-1) + 3y = 8<br />
solve the above equation for y:<br />
2 + 3y = 8<br />
3y = 6<br />
y = 2<br />
write the solution to the system as an ordered pair:<br />
(-1,2)<br />
check the solution obtained:<br />
first equation: Left Side: -2(-1) + 3(2)= 2 + 6 = 8<br />
Right Side: 8<br />
second equation: Left Side: 3(-1)-(2)=-3-2=-5<br />
Right Side: -5<br />
UNIT 9.SYSTEM OF EQUATIONS.. 10<br />
3x<br />
2x<br />
y<br />
3y<br />
5<br />
8
Change language